Presence of Multiple Tendinous Insertions of Palmaris Longus: A Unique Variation of a Retrogressive Muscle

Background: Palmaris longus, being the most variable muscle of the upper extremity is generally considered important morphologically rather than functionally. The palmar aponeurosis represents the distal part of the tendon of Palmaris longus.Case Details: We report here a unique case of palmaris longus presenting variation distally as its tendon divides to gain multiple attachments with the fascia covering the abductor pollicis brevis, flexor retinaculum and the tendon of flexor carpi ulnaris. In addition, it also continues as palmar aponeurosis as its normal course.Conclusion: Presence of this kind of variation might result in compression of the median and ulnar nerves and may aggravate the complications in case of inflammation of palmar aponeurosis thus mimicking the manifestations of Dupuytren’s contracture.Keywords: Palmaris longus, palmar aponeurosis, Dupuytren’s contractur

Case Report: Variant Origin of an Arterial Trunk from Axillary Artery Continuing as Profunda Brachii Artery- A Unique Arterial Variation in the Axilla and its Clinical Implications

Background: Axillary artery is known to show different variations mostly in its branching pattern. Similarly, the origin of profunda brachii is often encountered with abnormality. Therefore, when the vascular variations in the upper limb persist, mostly it is confined to its branching pattern followed by its variant origin. But, among all the reported variations of profunda brachii, its variant origin from the 3rd part of the axillary artery with common trunk for the branches of axillary artery is unique.Case Details: We report here an anomalous origin of profunda brachii as continuation of an arterial trunk arising from 3rd part of the axillary artery. This common trunk at its commencement passed between 2 roots of median nerve and gave branches of 3rd part of axillary artery before it continued as profunda brachii artery. The further course and branching pattern of profunda brachii were normal.Conclusion: Since the axillary artery is next choice of artery for arterial canulation in cardiopulmonary bypass procedures, prior knowledge of existence of such variation in its branching pattern helps in avoiding possible diagnostic or interventional therapeutic errors.Keywords: axillary artery, common trunk, profunda brachii, vascular variatio

Hydrogen Embrittlement of Inconel 718 Manufactured by Laser Powder Bed Fusion Using Sustainable Feedstock: Effect of Heat Treatment and Microstructural Anisotropy

This study investigated the in-situ gaseous (under 150 bar) hydrogen embrittlement behaviour of additively manufactured (AM) Inconel 718 produced from sustainable feedstock. Here, sustainable feedstock refers to the Inconel 718 powder produced by vacuum induction melting inert gas atomisation of failed printed parts or waste from CNC machining. All Inconel 718 samples, namely AM-as-processed, AM-heat-treated and conventional samples showed severe hydrogen embrittlement. Additionally, it was found that despite its higher yield strength (1462 ± 8 MPa) and the presence of δ phase, heat-treated AM Inconel 718 demonstrates 64% lower degree of hydrogen embrittlement compared to the wrought counterpart (Y.S. 1069 ± 4 MPa). This was linked to the anisotropic microstructure induced by the AM process, which was found to cause directional embrittlement unlike the wrought samples showing isotropic embrittlement. In conclusion, this study shows that AM Inconel 718 produced from recycled feedstock shows better hydrogen embrittlement resistance compared to the wrought sample. Furthermore, the unique anisotropic properties, seen in this study for Inconel 718 manufactured by laser powder bed fusion, could be considered further in component design to help minimise the degree of hydrogen embrittlement

An eccentric anatomical variation of palmar vascular pattern: Report of surgical challenging vascular variation

The knowledge of variations in the vascular architecture of hand is of great importance to surgeons, orthopedicians, and plastic surgeons in microsurgical procedures following crush injuries of the hand and amputations. The efficiency of collateral circulation in hand is essential in few peripheral vascular diseases like Raynaud′s disease and harvesting of the radial artery for the coronary bypass graft. During routine dissection of the right upper limb of a 55-year-old male cadaver, we observed that the superficial palmar arch (SPA) is formed by the ulnar artery and completed by the first dorsal metacarpal artery. After completing the arch, dorsal metacarpal artery continued as princeps pollicis artery for the thumb. The common palmar digital artery supplying the contiguous side of index and middle fingers passed through the neural loop formed by the proper digital nerve supplying the radial side of the middle finger and joined with the unusually large first palmar metacarpal artery before dividing into proper digital arteries. The first palmar metacarpal artery also gave origin to radialis indicis artery which in turn ran deep to tendons of the index finger to reach index finger. The common palmar digital artery supplying the contiguous side of middle and ring fingers also passed through the neural loop formed by the proper digital nerve supplying the ulnar side of the middle finger. The deep palmar branch of ulnar artery gave proper digital artery to little finger